Researchers have known that ocean temperatures are rising
but up until now haven't had any way of measuring the effects of this rise on
Antarctica's glaciers. New research will
now enable scientists to determine how quickly ice is melting under a rapidly
changing glacier.

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Martin Truffer, a physics professor at the University of
Alaska Fairbanks, and Tim Stanton, an oceanographer with the Naval Postgraduate
School, were able to look underneath the Pine Island Glacier on the West
Antarctic Ice Sheet and take exact measurements of the undersea melting
process.

"This particular site is crucial, because the bottom of
the ice in that sector of Antarctica is grounded well below sea level and is
particularly vulnerable to melt from the ocean and break up," said
Truffer, a researcher with UAF's Geophysical Institute. "I think it is
fair to say that the largest potential sea level rise signal in the next
century is going to come from this area."

Their measurements show that, at some locations, warm ocean
water is eating away at the underside of the ice shelf at more than two inches
per day. This leads to a thinning of the ice shelf and the eventual production
of huge icebergs, one of which just separated from the ice shelf a few months
ago.

Their work was highlighted in a recent issue of Science.
Both Truffer and Stanton, with other scientists from around the world, have
spent years studying the underside of the Antarctic ice shelf and glacier, but
the recent research took place in early 2013.

"UAF's part was to accomplish the drilling,"
Truffer said, crediting Dale Pomraning, with the GI's machine shop.

"We have a hot water drill that is modular enough to be
deployed by relatively small airplanes and helicopters, and we have the
expertise to carry this out." The drilling allowed the team to measure an
undersea current of warm water, driven by fresh water from the melting glacier.
The measurements will be used with both physical and computer models of ocean
and glacier systems, said Stanton. "These improved models are critical to
our improved ability to predict future changes in the ice shelf and glacial
melt rates of the potentially unstable Western Antarctic Ice Shelf in response
to changing ocean forces," Stanton said.